1. Field of the Invention
The present invention relates to a mobile communication system. More particularly, the present invention relates to an interference measurement method of a terminal for facilitating downlink transmission in the mobile communication system based on Distributed Antenna System (DAS) in which multiple antennas controlled by a base station are distributed within the service area of the base station.
2. Description of the Related Art
The mobile communication system has evolved into a high-speed, high-quality wireless packet data communication system to provide data and multimedia services beyond the early voice-oriented services. Recently, various mobile communication standards, such as High Speed Downlink Packet Access (HSDPA), High Speed Uplink Packet Access (HSUPA), Long Term Evolution (LTE), and LTE-Advanced (LTE-A) defined in 3rd Generation Partnership Project (3GPP), High Rate Packet Data (HRPD) defined in 3rd Generation Partnership Project-2 (3GPP2), and 802.16 defined in IEEE, have been developed to support high-speed, high-quality wireless packet data communication services. LTE is a communication standard developed to support high speed packet data transmission and to maximize the throughput of the radio communication system with various radio access technologies. LTE-A is the evolved version of LTE to improve the data transmission capability.
LTE is characterized by 3GPP Release 8 or 9 capable base stations and terminals (user equipment) while LTE-A is characterized by 3GPP Release 10 capable base stations and user equipment. As a key standardization organization, 3GPP continues standardization of the next release for more improved performance beyond LTE-A.
A recent issue under discussion is a technique for the terminal to measure and report interference to the base station in order to improve communication efficiency. However, the legacy terminal is configured to measure the interference caused by the transmission points of other cells but not those in the same cell, which may lead to acquiring an incorrect Signal-to-Interference ratio. Such incorrectness in Signal-to-Interference ratio is likely to cause significant problems in the LTE/LTE-A system adopting Adaptive Modulation and Coding (AMC) for adjusting the downlink data rate adaptively based on the Signal-to-Interference ratio.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.